Safety device



March 25, 1941. s. BUSH 2,236,307

SAFETY DEVICE Filed NOV. 6, 1939 Patented Mar. 25, 1941 UNITE STATES PATENT i OFFICE 6 Claims.

This invention relates to a new and improved apparatus Ato be used as a safety device for gas burners, such as stoves, `and it operates to auto- 'matically shut on" the flow of gas to the burner in case the flame is extinguished by anoverow of liquid.

The objects of this invention include the provi-v sion of an appar-atus to render the operation of a 4gas [burner safe `and to prevent the escape of .the gas when the llame is accidentally extinguished; the provision of such an apparatus in which a very small quantity of overflowing liquid will :cause the device to automatically close the main gas -cock and thereby prevent the unburned gas :from escaping; the provision of means to close a gas cock almost immediately upon the overflow of the liquid; and the provision of such a device which is simple in construction, inexpensive to manufacture, easily attachable to existing gas burners, and which may -be conveniently located in `a small space `as to be unnoticeable and out ofthe way.

Other objects and advantages of the invention n. will appear hereinafter.

Reference is .to be had to the accompanying drawing, in which Fig.V 1 isa front elevation of a gas stove embodying the present invention;

Fig. 2 is a side elevation of the device apart from the stove, looking in the direction of the yarrow 2 in Fig. 1;

Fig. 3 is a plan View, partly in section, of a part of th-e operating means;

Fig. 4 is a sectional view showing the weight held by the fuse;

Fig. 5 is a detail perspective view ofthe trip lever; and

Fig. 6 is a perspective view of the fuse.

It is well known that many accidents occur when the gas flame in a stove is extinguished by the boiling over of a liquid, and in some cases people have been asphyxiated by the resultant now of the gas. The present invention relates to a means to preveni-l such accidental asphyxiation.

Referring to the drawing in detail, it will be seen that a gas stove I8, having the usual burners and a gas inlet pipe I2 with a main gas cock I4, is provided with a drip pan I8, tilted slightly down from left to right in Fig. 1. At lthe lowest part of the drip pan there is provided a downwardly extending pipe I8 of small diameter and having both ends open. The pipe I8 may be secured to the stove as by a bracket 28. Naturally, a liquid in the drip pan will now down and into the pipe I8, as indicated by the arrow 22 in Fig. 2.

Below the pipe I8 and spaced vertically therefrom there is a box or container 24 attached to the stove by a bracket 26. This box may have a hinged cover 28, if desired, and is provided at its forward end with a slot 30, this slot extending a short way into the .bottom surface of the box so as lto provide an `undercut shoulder 32. A spring 34 is secured at one end to the rear of the box, and its other end is connected to one end of a wire rod 36 which is bent at 38 to form a shoulder opposite to the shoulder 32. The other end of the rod 38 is pvotally secured to the gas cock operating lever 4U, which is in open condition, Ias shown in Fig. 2.

A staple or other pintle 42 is located within the box- 24 and serves to secure a lever 44. This lever is reversely bent at 45 to form a bearing on which the lever 44 may rockin a vertical pl-ane, as shown by the arrow in Fig. 5. One end of the lever 44 is provided with a striking surf-ace 48, and the other end has an extending finger 50, which normally lies beneath the rod 36. It will be seen from this construction that the shoulder 38 in the rod 36 will ordinarily be held agains-t the shoulder 32 by the tension of the spring 34, but if the' lever 44 is pivoted about the staple 42, the nnger 58 will rise land pull the shoulder 38 out of engagement with the shoulder 32, in which case the spring 34 will quickly draw the rod 36 to the right in Fig. 2, and thus turn the lever 48 to the dotted line position and close .the cock I4.

Referring again to the box 24, i-t is seen that just above the striking surf-ace 48 of the lever 44, there is a round aperture .through which projects the lower end of a pipe 52. This pipe is just a little larger in diameter Ithan the pipe I8, and is arranged to telescope the end of the latter a short distance. At the lower end of the pipe 52 is a coil spring 54 secured by a collar 58 thereto, and this spring supports the pipe 52 for slidable Iaction through the aperture in the box. In the interior of the pipe 52 at its upper end there is an undercut shoulder 5l.

In Fig. 6 there is shown a fuse 58, which comprises a #cardboard or other -convenient cylinder 60, having a thin piece of tissue paper or other water soluble or destructible material 62 secured transversely across one end, as by glue or other means. When it is desired to insert the fuse, the pipe 52 is moved axially downwards against the -action of the spring 54, so that the ends of pipes 52 and I8 are slightly separated. Then the weight 64, about 15 penny weight, is inserted in the fuse, and it is placed so as to surround the end of pipe I8, and the pipe 52 is `allowed to telescope thereover as is clearly shown in Fig. 4, rthe shoulder holding the fuse in elevated position.

Having thus prepared the apparatus and the shoulders 32, 38 being engaged, the device is in condition to carry out its function. Thus, if a liquid on the stove extinguishes the flame, it will flow down the drip pan I6 into pipe I8 and dissolve or destroy the tissue 62, whereupon the weight 64 falls upon the striking surface 48 of the lever 44. As this depresses this end of the lever, the nger 56 rises, disengages the shoulder 38 and the spring 34 travels the rod 36, thus closing the cock I4. When the stove burners have been shut 01T, the pipe 52 is lowered, a new fuse and the weight 64 are placed in position, and the rod I36 is pulled out to again. engage shoulders 32 and 38.

From the description and operation ofV the device, it is seen that an automatic gas shut-off of simple and inexpensive nature has been provided, which renders it impossible to allow accidental asphyxiation. The entire device is located in a small space at one side of the stove and nothing about the latter is interfered with. The apparatus is simple and sure in its operation, and only a few drops o liquid are necessary to allow the weight to drop, since the tissue paper is easily soaked through.

Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what I claim is:

1. In a device of the class described having an apertured drip pan, a normally open valve, means to close said valve comprising a spring, a rod connected at one end to the spring and to the valve, said rod having means to hold the spring extended, a lever constructed and arranged to release said holding means upon a pivotal movement thereof, a liquid destructible support 10- cated directly below said aperture, a weight on said support and located above said lever, whereby the latter is pvoted to release said holding means upon the admission of liquid, and said spring contracts and withdraws said rod to close the valve.

2. In a device of the class described, a gas appliance having a normally open valve, means to close said valve upon the overflow of liquid on said appliance, comprising a tube extending down from said appliance, a second tube telescoping the lower end of said first tube and supported on a spring for vertical movement, a tissue paper element at the lower end of said rst tube, a weight supported thereby, and means to operate said valve closing means upon dissolution of said tissue paper by said liquid and consequent fall of said Weight.

3. In a device of the class described, a gas appliance, a gas line to said appliance, a valve in said line, a horizontal support, a Z-shaped rod normally engaging and stopped by said support and held in position by a tensioned spring at one end, the other end of said rod being connected to said valve, a trip having a finger under said rod, a weight above said trip, and a support for said weight which is adapted to be dissolved and thereby release said weight in the presence of a small amount of liquid, whereby said Weight will fall on said trip to lift said finger, releasing the rod from the support, and allowing the spring to retract and actuate said valve.

4. A device of the class described, as recited in claim 3, wherein the appliance is provided with an apertured drip pan, a tube extending from the aperture to a position just above the trip, and means in the tube to locate and hold the weight support.

5. In a device of the class described, a gas appliance having a manually openable valve, means to close said valve upon an overilow of liquid on said appliance, said means comprising a first tube extending downwardly from said appliance, a second tube in telescoping relation with said rst tube, a liquid destructible element arranged in said tubes adjacent their telescoping area, a weight on said element, and means to operate said valve upon destruction of said element by a liquid and consequent fall of said weight.

6. A device of the class described as recited in claim 5 in which one of said tubes is provided with a shoulder for reception and support of said element.

STANLEY BUSH. 

